Jennifer Wiseman works with the world’s most impressive telescope, but when she looks at the night sky above the rural Maryland home she shares with her husband, Mark Shelhamer, she prefers to admire it without the help of technology. “Sitting quietly outside and gazing up at a sky full of stars, contemplating the cosmos, is my favorite astronomical activity,” she says.

Wiseman and Shelhamer’s life together is full of astronomical activity. She is the senior project scientist for the Hubble Space Telescope at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, while he is serving a two-year term as chief scientist of the NASA Human Research Program at the Johnson Space Center in Houston.

Wiseman met Shelhamer in the fall of 1983, during her first semester at MIT. She had grown up on a cattle ranch in Mountain Home, Arkansas, and arrived on campus without a particular major in mind. “I wanted to try everything—all different kinds of classes, different extracurricular activities,” she says. While investigating her options, she attended an open house for freshmen at the Man Vehicle Laboratory, which was researching how astronauts adapt to spaceflight.

Shelhamer, a grad student in the lab, remembers talking with her that day. Wiseman signed up for a UROP, and for the next two years they studied how zero gravity affects astronauts’ sensorimotor perceptions. (In space, the brain relies more on visual information for orientation.)

After her sophomore year, Wiseman decided to focus on astronomy. On a field trip to the Lowell Observatory in Arizona a few months before earning her physics degree, she discovered a periodic comet on photographic plates taken by astronomer Brian Skiff. (Named 114P/Wiseman-Skiff, it’s believed to have spawned the first meteor photographed on Mars.) She then worked briefly at NASA’s Jet Propulsion Laboratory in Pasadena, California, and earned a PhD in astronomy from Harvard in 1995. For her doctoral thesis, she used radio interferometry to produce a complex mosaic map (which covers a larger area than a single telescope’s field of view) of Orion’s star-forming interstellar cloud; it made the cover of Nature.

Meanwhile Shelhamer, who had grown up in the steel town of Fairless Hills, Pennsylvania, and did his undergraduate work at Drexel, finished his ScD in biomedical engineering in 1990 and went to Johns Hopkins as a postdoc. He later became an associate professor at the medical school, studying sensory neurobiology along the way.

The two remained friends and were dating regularly by the mid-1990s, though they lived in different cities. When they married, in 1997, Shelhamer was living in Baltimore and Wiseman was close to finishing a fellowship at the National Radio Astronomy Observatory in Charlottesville, Virginia. Less than a year later, Wiseman received a Hubble fellowship in astronomy that she chose to do at Hopkins. “Up to then we had separate careers, separate lives,” she says. “That was the first time we made a conscious decision to be in the same place, and it worked out wonderfully.”

Wiseman was a test subject for Shelhamer’s research on NASA’s Vomit Comet in 2003.

They put down roots in the Baltimore area, buying a 1970s colonial that’s now home to four elderly cats and two careers’ worth of space-related books, photos, and memorabilia, including a collection of souvenir pins from the Mercury, Gemini, Apollo, and space shuttle missions and a photo of the couple floating inside the so-called Vomit Comet, NASA’s parabolic flight aircraft. One bedroom is allocated to Shelhamer’s short-wave radio hobby: equipment from ships in the 1950s and ’60s shares shelf space with 40 communications receivers, and a workbench is crowded with wires, spare parts, oscilloscopes, and more.

Though Wiseman, 49, and Shelhamer, 55, have NASA in common, their occupations are quite different. She is concerned with deep space, while he focuses on the effects of space travel on humans. That distinction provides fodder for complex and often enlightening conversations. They enjoy “a friendly continuing discourse about what kind of space exploration gives us the most interesting return,” Wiseman says. “Is it sending humans into space, or is it investigating without humans by sending probes and telescopes where we can explore farther out?”

Wiseman is a senior astrophysicist at NASA and has been the Hubble’s senior project scientist since 2010. She ensures that the telescope, last serviced by astronauts in 2009 and now projected to remain functional until at least 2020, is as scientifically productive as possible. Her job involves hard science as well as reviewing information about cosmic discoveries coming from the telescope and explaining those discoveries to NASA officials and the public. Lately Hubble has collected some of the first data ever about the atmospheres of planets outside our solar system, or exoplanets, and its newest camera has captured images of galaxies so distant that their light has taken more than 13 billion years to reach us. “That means that we are seeing infant galaxies as they looked not too long, astronomically speaking, after the beginning of the universe,” she says.

At Hopkins, Shelhamer studied humans’ vestibular (balance) and oculomotor (eye movement) systems and how they adapt to conditions in space. He went on leave in June 2013 to join NASA’s Human Research Program, whose goal is to figure out how astronauts can eventually survive a journey to Mars. (NASA hopes such a trip could happen about 20 years from now and expects that it would take three years.) Shelhamer helps determine what human research projects NASA should fund and serves as the program’s ambassador to the scientific community and the public. He is now based, professionally at least, in Houston.

Shelhamer applied for the position at the Johnson center figuring it would be a good way to make new contacts. He didn’t believe he was qualified, and he didn’t want to leave his wife and home for two years. When he got the offer, he was floored. “I was pacing,” he says. “I said the time isn’t right, I’m going to tell them I’m going to wait.” Wiseman, who thought he was a great fit for the job from the start, countered with an argument he couldn’t resist: “You’ll be overseeing experiments on the space station. How cool is that? You have to do it.”

More than a year into the job, Shelhamer is enjoying what Wiseman has called his “grand adventure.” “It’s different from doing basic science in the lab, where you can pursue new findings and try things just because they are interesting,” he says. “Our program is much more focused, and balancing innovative science with the need to get answers in a timely manner is one of my main concerns.” Recently greenlighted projects include examining the combined effects of weightlessness and radiation on blood vessels, studying how vitamins degrade in space food over time, and determining predictors of behavioral and stress problems in crew members.

Shelhamer appreciates having a wider sphere of influence than he did as a researcher. “Here, there are a lot more people who want a piece of me, who want to run an idea by me,” he says. “I gotta say, that’s kind of nice.” He’s also enjoying the respite from grant writing.

Travel has always been a big part of both their careers, and despite Shelhamer’s initial trepidation about being apart, they’ve dealt with that successfully before. When they are both home, they spend time together relaxing on the front porch with their cats (and perhaps their laptops) or retreating to the basement, where Wiseman runs on the treadmill while Shelhamer, an avid jazz drummer, provides live workout music.

Very rarely, their work lives intersect. Earlier this year Wiseman was giving talks in Houston, so she checked out Shelhamer’s new office. As they drove through the front gate at Johnson, both flashed their NASA badges to get in.